Your body was built by the hard battles and challenges you have faced into the mountain of stone it is today. You gain +1 to your Constitution Score. On top of that, you gain 3 Vigor Points to use in the below mentioned ways.
When taking damage, making a Constitution check, or making a Constitution Save, you may expend any number of Vigor points up to the maximum available to you as a free action to roll 1 health dice per the Vigor point expended to heal the damage dealt or add to the check or save roll. This feature must be decided before the outcome of the check or save is determined, or after damage is done. The user must expend all Vigor points to regain them, and may only regain them after a Long Rest.